Lights blinding pedestrians

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Mr Tom
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Re: Lights blinding pedestrians

Post by Mr Tom »

simonineaston wrote: 24 Sep 2022, 9:11am This subject has been a bugbear of mine for years - at least as long as high brightness front lamps came to market. It's partic. a problem on shared use paths, as remarked by mr tom. It's one of the reasons I've always bit the bullet and bought b&m lamps, with their carefully designed beam pattern. I had thought I was doing the right thing and that by employing b&m's lamps, I was reducing the likelihood of dazzling those travelling (either by foot or on a bike) towards me to a minimum.
So I'm disappointed to learn that mr t's b&m lamps appear to be problematic. When I've set up mine (I have a less poweful model on the Brompton and a brighter one on the Moulton) I've seen that the beam pattern has quite a sharp cut-off at top and have hitherto been confident that the cut-off means I'm not dazzeling others...
I remain furious that the doughnuts who buy super-bright lamps, with no beam control built in, have not the wit to work out the effect their lamps are having on the night vision of oncoming travellers and am super embarassed to find that it turns out I might be one of these knuckle scrapers myself !!
Don't worry yet! As I said I used to set it up pretty carefully in the winter but haven't really been going on paths much this year and so it's just been there to be seen by. I think maybe I had the bright spot too far forwards, so the cut-off was too high. I'll try to dial it in and see where the beam cuts off.
PH
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Re: Lights blinding pedestrians

Post by PH »

jois wrote: 24 Sep 2022, 1:57am
interestedcp wrote: 23 Sep 2022, 11:56pm I think what the pedestrians are experiencing aren't blinding as such. B&M lights and all similar STZVO approved lights, only emits 4 Lux above the cut off point of the beam. However, the actual lamp is still very bright to look directly at, especially with night accustomed eyes. In other words, the light feels intense, but unless you actually lit up their faces with your beam, it wasn't technically blinding.
The only way you can see the light is if photons hit your eye. This is only possible if you are in the beam of light. It may not be the brightest part of the beam, but a beam never the less
I think interestedcp has it right. I'm not sure of the physics or biology, but there's a difference between seeing how bright a light is and being dazzled by it, if not then driving at night would be impossible. Even when it comes to anti-social lights, I find them easier to deal with when walking than riding. No less annoying, it's just easier to avert my eyes while continuing safely.
I think some people are more sensitive than others, as pointed out in another thread there's also those who'd eyes are unavoidably below the cut off. There are also those who like to make a fuss, even when it isn't warranted. At the risk of seeming complacent, we can only do the best with what's available, knowing the issues and mitigating them is the right thing to do, we have to accept that might not be perfect for everyone.
jb
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Re: Lights blinding pedestrians

Post by jb »

A vastly more powerful car headlight will dazzle less than a LED bike light that has a small point source. Especially when seen at night. Because the concentration of photons hitting the retina is higher.
At least the B & M lights spread the beam over a wider reflector.
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jois
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Re: Lights blinding pedestrians

Post by jois »

PH wrote: 24 Sep 2022, 11:13am
jois wrote: 24 Sep 2022, 1:57am
interestedcp wrote: 23 Sep 2022, 11:56pm I think what the pedestrians are experiencing aren't blinding as such. B&M lights and all similar STZVO approved lights, only emits 4 Lux above the cut off point of the beam. However, the actual lamp is still very bright to look directly at, especially with night accustomed eyes. In other words, the light feels intense, but unless you actually lit up their faces with your beam, it wasn't technically blinding.
The only way you can see the light is if photons hit your eye. This is only possible if you are in the beam of light. It may not be the brightest part of the beam, but a beam never the less
I think interestedcp has it right. I'm not sure of the physics or biology, but there's a difference between seeing how bright a light is and being dazzled by it, if not then driving at night would be impossible. Even when it comes to anti-social lights, I find them easier to deal with when walking than riding. No less annoying, it's just easier to avert my eyes while continuing safely.
I think some people are more sensitive than others, as pointed out in another thread there's also those who'd eyes are unavoidably below the cut off. There are also those who like to make a fuss, even when it isn't warranted. At the risk of seeming complacent, we can only do the best with what's available, knowing the issues and mitigating them is the right thing to do, we have to accept that might not be perfect for everyone.
Yes there is a difference. But non of the terms being used have any fixed definition . Dazzled /blinded can be much the same thing dependent on who is talking.

My biggest issue with the very variable light and beams in use is it's very difficult to judge distance. Half a candle power on top of you or a mobile sun half a mile away. There seems to be no onus felt by the mobile sun brigade to to turn down or redirect the beam.

If I'm walking I just shine my ultra bright torch in their face. Which isn't the smartest thing to do as now nobody can see where they are going. But it seems to make them cross and me feel better.
Biospace
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Re: Lights blinding pedestrians

Post by Biospace »

If a light is blinding pedestrians on a level path, the beam is angled way too high and will be dazzling motorists as much or more if used on the road. It's well worth finding somewhere properly dark to angle a beam correctly, our own vision improves as beam cut-off is a little way up the road rather than somewhere in a distant hedge. A slightly misty air makes this even easier.

Lights designed to throw an intense light well ahead, towards the top of the beam, need even more careful setting up than a lamp with a conventional circular beam, since the moment the cut off rises a little higher than usual, for example over bumps or gentle hill crests, someone approaching receives a sudden, very bright light in their eyes, which is what we try to avoid for our own safety as much as others' discomfort. A lamp which vibrates can produce a flashing effect, the sort which generates an automatic pre-warning on tv.

This is the problem with the modern car headlight, which I find intensely annoying when set up incorrectly. The idea of a sharp cut off is to allow higher speeds when driving a car on dipped beam, the traditional British headlight grew 'softer' and less intense towards its edges. Despite remote control of headlights' angle (to compensate for loaded vehicles), many motorists are unaware they're dazzling others (can they not see where their lights are falling?), or don't understand their vehicles' secondary controls.

interestedcp wrote: 23 Sep 2022, 11:56pm So to a certain extent it is hard to avoid that those pedestrians that don't avert their eyes from your LED feels that your light is strong and blinding. Perhaps pointing the light very downwards on unlit shared paths, but then again, you may risk hitting pedestrians.
This is completely wrong. The whole point of headlamp design is that they don't dazzle oncoming motorists or others, but throw plenty of light forwards onto the road.

PH wrote: 24 Sep 2022, 11:13am
I think some people are more sensitive than others, as pointed out in another thread there's also those who'd eyes are unavoidably below the cut off. There are also those who like to make a fuss, even when it isn't warranted. At the risk of seeming complacent, we can only do the best with what's available, knowing the issues and mitigating them is the right thing to do, we have to accept that might not be perfect for everyone.
The thing is, an oncoming headlight which dazzles without warning for more than a couple of seconds can cause an accident if there's not time to slow sufficiently. Taking the attitude that we should just accept wrongly adjusted headlights will surely only allow matters to grow worse?
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Sum
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Re: Lights blinding pedestrians

Post by Sum »

Mr Tom wrote: 24 Sep 2022, 10:49am Don't worry yet! As I said I used to set it up pretty carefully in the winter but haven't really been going on paths much this year and so it's just been there to be seen by. I think maybe I had the bright spot too far forwards, so the cut-off was too high. I'll try to dial it in and see where the beam cuts off.
If you don't know where the cut-off of the beam is ending up on the path then it is possible that it might be set too high, and it is certainly worth checking.

Looking at where the brightest part of the beam is shining on the path (as per your OP) might not be good enough. If I understand the StVZO correctly, the 'regs' specify the light should not be more than 2.0 lux (at 10m) at 3.4° above the brightest part of the beam. Hence the cut-off can be anywhere in the transition region (+0 to +3.4°) above the brightest part. So, if you did have brightest part of the beam shining at 10 metres on the path ahead, then this might suggest your light was adequately dipped, however it doesn't have to take much to get it wrong; If the brightest part was actually shining ~13 metres ahead then the cut-off could have been shining horizontally maybe*, and if the brightest part was shining on the path even further way then the cut-off could have been shining up into the sky.

*Exact numbers will depend on where the cut-off lies in the transition region (+0 to +3.4°) above the brightest part of the beam, and how high the headlamp is mounted. Hence for me at least, the best way to aim my headlamp was by looking at the cut-off and making sure that that ends up on the road somewhere.
SA_SA_SA
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Re: Lights blinding pedestrians

Post by SA_SA_SA »

Mr swhs thought the German Stzvo section on aim was hopelessly ambiguous ( the 3.4 degress dip at 10m is part of the testing setup, but the aim section mentioned the middle of be beam which was then not clearly defined...) but it seems that aim section was deleted (but not replaced with new guidance on aim, but mr swhs suggested a the cutoff hitting ground at a max of 40-50m which compares with car dipped headlamp aim max range). https://swhs.home.xs4all.nl/fiets/tests ... ex_en.html

10m is much too short a distance to be able to see ahead. Car dipped lamps can illuminate much further and i think the minimum dip for is something like a 1.3% drop (why not degrees) , but I think equates to a 1ish degree minimum dip.

The CJ mentioned setting his lamp with a 2 degree dip somewhere on this forum.
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mattsccm
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Re: Lights blinding pedestrians

Post by mattsccm »

Not saying that many a light is not used considerately but bear in mind that a near useless Wonderlight might be considered blinding if its hinders your vision.
PH
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Re: Lights blinding pedestrians

Post by PH »

Biospace wrote: 24 Sep 2022, 11:56am
PH wrote: 24 Sep 2022, 11:13am At the risk of seeming complacent, we can only do the best with what's available, knowing the issues and mitigating them is the right thing to do, we have to accept that might not be perfect for everyone.
Taking the attitude that we should just accept wrongly adjusted headlights will surely only allow matters to grow worse?
That isn't what I said. Neither is it my attitude, indeed you'll find I've been vocal on this forum for a number of years criticising those who don't use lights responsibly and that includes being correctly adjusted.
What I am saying, is that some people will find any bike with any light coming towards them objectionable, that's unfortunate, but unavoidable.
Jdsk
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Re: Lights blinding pedestrians

Post by Jdsk »

Mr Tom wrote: 24 Sep 2022, 10:49amDon't worry yet! As I said I used to set it up pretty carefully in the winter but haven't really been going on paths much this year and so it's just been there to be seen by. I think maybe I had the bright spot too far forwards, so the cut-off was too high. I'll try to dial it in and see where the beam cuts off.
Sounds good. Could you include some before and after photos, preferably with a pedestrian in an appropriate position?

Thanks

Jonathan
peetee
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Re: Lights blinding pedestrians

Post by peetee »

I’m my experience many LED bike and car lights have ‘spill’ that is too intense. In practice these lights are angled correctly but the LED bulb is still visible beyond the concentrated area and that constitutes a very small but very strong light source that I find to be too intense.
It could well be part of the design as forward vision for the cyclist is important but so too is side-on or front three-quarter visibility of the cyclist for traffic approaching from joining roads.
I also find the same with some household bulbs. My daughter uses a lamp when sitting to the side of me which I find uncomfortable and distracting even when at an angle of 90 degrees or so.
The older I get the more I’m inclined to act my shoe size, not my age.
Biospace
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Re: Lights blinding pedestrians

Post by Biospace »

PH wrote: 24 Sep 2022, 1:36pm
Biospace wrote: 24 Sep 2022, 11:56am
PH wrote: 24 Sep 2022, 11:13am At the risk of seeming complacent, we can only do the best with what's available, knowing the issues and mitigating them is the right thing to do, we have to accept that might not be perfect for everyone.
Taking the attitude that we should just accept wrongly adjusted headlights will surely only allow matters to grow worse?
That isn't what I said. Neither is it my attitude, indeed you'll find I've been vocal on this forum for a number of years criticising those who don't use lights responsibly and that includes being correctly adjusted.
What I am saying, is that some people will find any bike with any light coming towards them objectionable, that's unfortunate, but unavoidable.
I read your comments wrongly, in that case.

From what you've said directly above, is it the way in which bike lights can move around more than other vehicles headlights which makes you believe some will always find any bike light coming towards them irritating? I have problems with any headlight if it's directed in my eyes, whether someone's headtorch, a bike headlamp, car or whatever.
mattsccm
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Re: Lights blinding pedestrians

Post by mattsccm »

There seems to be the suggestion, nay apologies, that bike lights are too bright. Some are and some are pointing the wrong direction but to some extend that is tough. My motorbike has dim pre halogen lights. It also has them set low enough that they don't get any where near the position regarded as correctfor the MOT. Yet they are still "blinding" if looked at directly. My crappy Never ready head torch is the same. Any lightwill "blind" Yeah :roll: if you look at it directly or it's dark. My night vision is buggered by my bike computer. Meet a pedestrian on a unlit they will be dazzled. For a few second maybe.
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Sum
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Re: Lights blinding pedestrians

Post by Sum »

SA_SA_SA wrote: 24 Sep 2022, 12:52pm Mr swhs thought the German Stzvo section on aim was hopelessly ambiguous ( the 3.4 degress dip at 10m is part of the testing setup, but the aim section mentioned the middle of be beam which was then not clearly defined...) but it seems that aim section was deleted (but not replaced with new guidance on aim, but mr swhs suggested a the cutoff hitting ground at a max of 40-50m which compares with car dipped headlamp aim max range). https://swhs.home.xs4all.nl/fiets/tests ... ex_en.html

10m is much too short a distance to be able to see ahead. Car dipped lamps can illuminate much further and i think the minimum dip for is something like a 1.3% drop (why not degrees) , but I think equates to a 1ish degree minimum dip.

The CJ mentioned setting his lamp with a 2 degree dip somewhere on this forum.
The OP mentioned that it was the brightest part of their headlamp was shining on the path was about 10 metres ahead (they didn't seem to know where the cut-off was ending up on the path). Depending upon where the cut-off lies in the transition region (+0 to +3.4° above the brightest part of the beam), then the cut-off may be several tens of metres away, or even shining up into the sky if the 10m estimate was more than a little out.
Tangled Metal
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Re: Lights blinding pedestrians

Post by Tangled Metal »

I bought a raveman pr1600 light. It has two LEDs, one full beam the other has a bid freznel lens. It's used with just the freznel lensed light up to 900 lumens and both up to 1600 lumens. This effectively allows me to use full beam at a couple of really dark and heavily potholed sections where there is little chance of dazzling others. No others around to dazzle when I'm there. But in other areas with better road surfaces and more users I keep it dipped, often less than the full 900 lumens in this mode.

I think there's more lights with this dipped headlight option just like cars have, but mine still isn't legal to the German standard. It is possibly good enough though. Works for me and the remote button means I'm quicker at dipping my lights than when in a car.

BTW anyone else see (or not very well) car drivers who don't feel the need to dip their lights for cyclists even pedestrians?
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